The second `IE` for alkali metals shows a jump while the third `IE` for alkaline metals shows a jump. Explain.

Explanation

The alkali metals have `ns^(1)` configuration while alkaline earth metals have `ns^(2)` configuration.
So after `IE_(1)`, the alkali metal attain the inert gas configuration while the alkaline earth metals attain it after `IE_(2)`. Now the removal of electron from a noble gas configuration requires high `IE_(1)` so there is a jump in the `IE_(2)` for alkali and `IE_(3)` for alkaline earth metals.